

def x(num):
    res = 1
    for i in range(1, num+1):
        res *= i
    return res


def y(num):
    res = 1
    i = 1
    while i <= num:
        res *= i
        i += 1
    return res

z = lambda num: num if num == 1 else num * z(num-1)

print(z(5))
print(f'5的阶乘{x(5)}, {y(5)}')
